In recent years, solar cells have been drawing attention as a low environmental-load energy source. Especially, solar cells including a substrate made of a semiconductor material such as a crystalline silicon substrate have been drawing attention.
In manufacturing such a solar cell including a substrate made of a semiconductor material, it is necessary to perform a step of wet etching the substrate such as a step of forming a relief structure called a texture structure on a surface of the substrate made of the semiconductor material (see Japanese Patent Application Publication No. Hei 10-303443 (Patent Document 1), for example).